Governors for internal combustion engines



Nov. 7, 1961 c. N. GOLDSMITH ETAL 6 GOVERNORS FOR INTERNAL COMBUSTION ENGINES Filed March 7, 1960 United Smtes Patent Ofice 3,007,463 Patented Nov. 7, 1961 3,007,463 GOVERNORS FOR INTERNAL COMBUSTION ENGINES Charles Norman Goldsmith, Shoreham-by-Sea, and Kenneth Chisholm Barnes-Moss, Hove, England, assignors t C.A.V. Limited, London, England Filed Mar. 7, 1960, Ser. No. 13,043 Claims priority, application Great Britain Mar. 11, 1959 1 Claim. (Cl. 123-140) This invention relates to governors for internal combustion engines of the compression ignition type, the governor being of the kind comprising a chamber which is divided into two compartments by a spring loaded diaphragm or the like connected to a control member of a pump for supplying liquid fuel to the engine, one of the compartments of the chamber being adapted for connection to a point in the air-intake system of the engine so that the supply of fuel to the engine will be varied in response to changes in the pressure in the air-intake system.

The object of the invention is to combine with such a governor convenient means for interrupting the supply of fuel to the engine in the event of the engine commencing to rotate in the reverse direction, with consequent substantial increase in the pressure in the air-intake system.

According to the invention a governor of the kind specified has combined therewith a valve through which the other compartment is adapted to be connected to a point in the air-intake system which, when the engine is operating, will be at a higher pressure than the point to which said one compartment is connected, said valve normally serving to place said other compartment in communication with atmosphere but being operable by a change from a negative to a positive pressure in the air-intake system to close the communication with atmosphere and to connect said other compartment to the system, thereby causing the diaphragm or the like to be moved to a position to interrupt the supply of fuel to the engine.

In the accompanying drawings FIGURE 1 is a partsectional side elevation of an example of the invention, and FIGURES 2 and 3 respectively are sectional views of two alternative forms of valve for incorporation in the example shown in FIGURE 1.

Referring to the drawing the governor comprises a chamber 4 which is divided into two compartments 5, 6 by a diaphragm 7. The diaphragm is connected to a rack bar or other control member 8 of a fuel pump 9, and is spring loaded toward a maximum fuel supply position by means of a spring 10 acting on the diaphragm.

The compartment is connected through a pipe 11 to the air inlet 12 of an air intake manifold 13 adjacent a butterfly valve 14. The compartment 6 is connected through a valve 1'5 to a point in the manifold 13 which, when the engine is in operation, is at a higher pressure than the air inlet 12 to which the pipe 11 is connected, this higher pressure being due to the venturi effect within the air inlet.

Referring to FIGURE 2 of the drawings, the valve 15 comprises a body formed in three parts 16 16 and 16. In the part 16 is formed an inlet which is normally in communication with an outlet to atmosphere 16 through a filter 17. Clamped between the parts 16 and 16 of the body is a flexible diaphragm 18 which normally bears against a seating 16 formed on the part 16 and surrounding an outlet 16 which is adapted for connection to the manifold 13. A further seating 16 is formed on the part 16 at the opposite side of the diaphragm to the seating 16.

When the engine is rotating in the correct direction there is a negative pressure within the inlet 12 which is applied to the compartment 5. There is also a negative pressure in the manifold 13 which serves to hold the diaphragm 18 against the seating 16 thereby maintaining communication between the compartment 6 and atmosphere. Since the pressure in the inlet 12 will vary with speed the diaphragm and rack '8 will be moved in accordance with speed to control the supply of fuel to the engine in known manner. However, should the engine start to rotate in the reverse direction a positive pressure will be created in the manifold 13. The effect of this positive pressure is to move the diaphragm 18 away from the seating 16 and into contact with the seating 16 thereby closing the communication between the compartment 6 and atmosphere and opening this compartment to the positive pressure in the manifold 13 through a port or ports 16 in the valve port 16. As a result the diaphragm 7 will be moved quickly to the left as viewed in FIGURE 1 to interrupt the supply of fuel to the engine.

In the modified valve 15 shown in FIGURE 3 (wherein like references are used to those used in FIGURE 2 where applicable) the seating 16 is omitted and replaced by a separate non-return ball valve 19 which is springloaded into contact with a seating 19 in the outlet 16 In other respects the Working of the valve shown in FIG- URE 3 is similar to that shown in FIGURE 2. For this purpose the interior of the valve part 16 is in constant communication with the interior of the valve part 16 through a port or ports 16 between fixed arcuate members 16 contained within the valve part 16 and serving to clamp the diaphragm 18 in position.

Having thus described our invention what we claim as new and desire to secure by Letters Patent is:

A governor for an internal combustion engine of the compression ignition type to which liquid fuel is supplied by a pump having an axially movable output control rod, and to which air is supplied from an air intake manifold having an air inlet, comprising in combination with the output control rod of the pump, and the air intake manifold of the engine, a pressure-responsive member connected to one end of said rod for imparting axial movement thereto, a chamber containing said pressure-responsive member and divided thereby into first and second compartments, a compression spring contained in the first compartment of said chamber, and acting on said pressure-responsive member in the direction for urging said rod towards a maximum fuel supply position, a valve which is connected to the second compartment of said chamber, and through the medium of which said second compartment normally communicates with the ambient atmosphere, a first pipe connecting said first compartment to the air inlet of said manifold, and a second pipe connecting said valve to said manifold at a position spaced from said inlet, said valve having movable means for interrupting communication between said second compartment and the ambient atmosphere, and establishing communication between said second compartment and said second pipe, in response to a change from negative to positive pressure within said manifold, whereupon said pressure-responsive member is moved against the action of said spring by the pressure in said second compartment, and thereby moves said rod to a position for causing the fuel delivery of the pump to be interrupted.

Weber et al Dec. 12, 1939 Peras Dec. 20, 1955 

